HUNTSVILLE, Ala. (Feb. 6, 2003) - The sharp
image of a galaxy halfway across the universe might shred modern theories about
the structures of time and space, and change the way astrophysicists view the
"Big Bang," according to two scientists at The University of Alabama in
Huntsville (UAH).

Their findings might also provide important clues to
(and cause significant upheaval among) researchers trying to merge two of the
most significant scientific theories of the last century: Einstein's theory of
general relativity and Planck's theory of the quantum.

We present a method of directly testing whether time continues to have its usual
meaning on scales of <= t_P = sqrt(hbar G/c^5) ~ 5.4E-44 s, the Planck time.
According to quantum gravity, the time t of an event cannot be determined more
accurately than a standard deviation of the form sigma_t/t = a_o (t_P/t)^a,
where a_o and a are positive constants ~1; likewise distances are subject to an
ultimate uncertainty c \sigma_t, where c is the speed of light. As a
consequence, the period and wavelength of light cannot be specified precisely;
rather, they are independently subject to the same intrinsic limitations in our
knowledge of time and space, so that even the most monochromatic plane wave must
in reality be a superposition of waves with varying omega and {\bf k}, each
having a different phase velcocity omega/k. For the entire accessible range of
the electromagnetic spectrum this effect is extremely small, but can
cumulatively lead to a complete loss of phase information if the emitted
radiation propagated a sufficiently large distance. Since, at optical
frequencies, the phase coherence of light from a distant point source is a
necessary condition for the presence of diffraction patterns when the source is
viewed through a telescope, such observations offer by far the most sensitive
and uncontroversial test. We show that the HST detection of Airy rings from the
active galaxy PKS1413+135, located at a distance of 1.2 Gpc, secures the
exclusion of all first order (a=1) quantum gravity fluctuations with an
amplitude a_o > 0.003. The same result may be used to deduce that the speed
of light in vacuo is exact to a few parts in 10^32.